US4412354A - Millimeter-wave stripline planar mixer - Google Patents

Millimeter-wave stripline planar mixer Download PDF

Info

Publication number
US4412354A
US4412354A US06/364,289 US36428982A US4412354A US 4412354 A US4412354 A US 4412354A US 36428982 A US36428982 A US 36428982A US 4412354 A US4412354 A US 4412354A
Authority
US
United States
Prior art keywords
signal
stripline
further characterized
housing member
planar microstrip
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US06/364,289
Other languages
English (en)
Inventor
Chi P. Hu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Stellex Microwave Systems Inc
Original Assignee
Honeywell Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Honeywell Inc filed Critical Honeywell Inc
Assigned to HONEYWELL INC., A CORP. OF DE. reassignment HONEYWELL INC., A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: HU, CHI P.
Priority to US06/364,289 priority Critical patent/US4412354A/en
Priority to EP83103016A priority patent/EP0091042B1/en
Priority to DE8383103016T priority patent/DE3364147D1/de
Priority to JP58055353A priority patent/JPS58202604A/ja
Publication of US4412354A publication Critical patent/US4412354A/en
Application granted granted Critical
Assigned to WATKINS-JOHNSON COMPANY, A CORP. OF CA reassignment WATKINS-JOHNSON COMPANY, A CORP. OF CA ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: HONEYWELL, INC.
Assigned to STELLEX MICROWAVE SYSTEMS, INC., A CALIFORNIA CORPORATION reassignment STELLEX MICROWAVE SYSTEMS, INC., A CALIFORNIA CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: WATKINS-JOHNSON COMPANY, A CALIFORNIA CORPORATION
Assigned to FIRST UNION COMMERCIAL CORPORATION reassignment FIRST UNION COMMERCIAL CORPORATION SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: STELLEX MICROWAVE SYSTEMS, INC.
Assigned to STELLEX MICROWAVE SYSTEMS, INC. reassignment STELLEX MICROWAVE SYSTEMS, INC. RELEASE Assignors: FIRST UNION COMMERCIAL CORPORATION, AS COLLATERAL AGENT
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D9/00—Demodulation or transference of modulation of modulated electromagnetic waves
    • H03D9/06—Transference of modulation using distributed inductance and capacitance
    • H03D9/0608—Transference of modulation using distributed inductance and capacitance by means of diodes
    • H03D9/0633—Transference of modulation using distributed inductance and capacitance by means of diodes mounted on a stripline circuit
    • H03D9/0641—Transference of modulation using distributed inductance and capacitance by means of diodes mounted on a stripline circuit located in a hollow waveguide
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D2200/00—Indexing scheme relating to details of demodulation or transference of modulation from one carrier to another covered by H03D
    • H03D2200/0001—Circuit elements of demodulators
    • H03D2200/0017—Intermediate frequency filter
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D7/00—Transference of modulation from one carrier to another, e.g. frequency-changing
    • H03D7/14—Balanced arrangements
    • H03D7/1408—Balanced arrangements with diodes
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D9/00—Demodulation or transference of modulation of modulated electromagnetic waves
    • H03D9/06—Transference of modulation using distributed inductance and capacitance
    • H03D9/0608—Transference of modulation using distributed inductance and capacitance by means of diodes
    • H03D9/0633—Transference of modulation using distributed inductance and capacitance by means of diodes mounted on a stripline circuit

Definitions

  • This invention relates in general to a millimeter-wave signal mixer, i.e., the mixing of a local oscillator signal with an R.F. or radio frequency signal to produce an intermediate frequency or I.F. signal, the mixer employing beam lead schottky-barrier diodes in a balanced configuration.
  • the present invention provides a novel type of mixer in which the band width and operating frequency limitations of prior art apparatus are avoided.
  • the full wave band mixer capability is especially desirable for applications in radar warning, EHF, EMS nd ELINT applications that must serve a large band width searching for possible emitters in the frequency spectrum.
  • FIG. 1 is an exploded isometric view of the apparatus comprising the invention
  • FIG. 2 is a view of the back side of the flat stripline base member of FIG. 1;
  • FIG. 3 is an enlargement from FIG. 1 showing the connection details of the pair of mixer diodes
  • FIG. 4 is an enlargement from FIG. 1 showing the details of the connection from the microstrip to the I.F. output means;
  • FIG. 5 is a cross-section of the apparatus of FIG. 1 when assembled as taken along the axis 25' of the R.F. port 25.
  • reference numeral 10 depicts a millimeter-wave stripline planar wide-band mixer comprising an elongated housing member having a first end 40 and a second end 41.
  • the housing member comprises first and second rectangularly shaped block members 12 and 32 each having a flat face surface 13 and 33 respectively.
  • Block member 12 and 32 are adapted to be held together with surfaces 13 and 33 in abutting relationship by suitable screw means, not shown, which pass through suitable apertures 19, 20, 21 and 22 in block 12 into suitable threaded apertures 19a, 20a, 21a and 22a in block 32.
  • Elongated housing member 12/32 is provided with an internal elongated enclosure extending from one end to the other. More specifically, the elongated enclosure takes the form of a pair of relatively shallow recesses 18 and 42 in blocks 12 and 32 respectively which extend from one end of the housing member 12/32 to the other and, when, as aforesaid, the two blocks 12 and 32 are assembled in abutting relationship, form the aforesaid elongated enclosure. Positioned within the enclosure is an elongated flat stripline base member 50. As depicted in FIG. 1, flat stripline base member 50 has a flat elongated shape with a core member made out of an appropriate insulative material, such as soft duroid.
  • a first relatively deep recess 14 is provided in block member 12 in register with the enclosure and extending from said enclosure into the block member along all of one side or along the entire length of said stripline member.
  • the depth of the rectangular recess 14 is equivalent to the half of the broad side dimension of the waveguide. So is true for the recess 34.
  • a second relatively deep recess 34 is provided in the housing block 32; this recess however only extends along a relatively short portion of the other side of the stripline member beginning at end 40 of the housing member.
  • the recess 34 terminates with an end wall 36.
  • the depth of recess 34 is the same as recess 14.
  • the length of recess 34 is typically longer than three wavelengths of the local oscillator frequency. Therefore, it is long enough to accommodate a waveguide-to-microstripline transition 54/55 on the stripline member.
  • the two relatively deep recesses 14 and 34 collectively define a port to which may be applied a local oscillator frequency, this being depicted in FIG. 1 with the legend "L.O. port".
  • Conventional means, not shown, are provided for applying a local oscillator (L.O.) signal to the first end of the housing blocks 12/32, said means including a plurality of threaded apertures 45 in the end faces of housing blocks 12 and 32 for attachment thereto of standard microwave adaptor apparatus.
  • a radio frequency (R.F.) port 25 passes completely through housing block 12 along an axis 25' which is at right angles to the axis of the enclosure 18/42.
  • the axis 25' is adapted to pass through the center of the stripline base member 50/51.
  • the R.F. port extends along axis 25' into housing block 32 extending approximately a quarter wave length (of the R.F.) beyond said elongated enclosure.
  • the R.F. port has a rectangular shape having a width 26, a height 27 and a depth 28.
  • the R.F. recess in block 32 has corresponding dimensions 26 and 27 for width and height, respectively; the depth 29 is, as aforesaid, a quarter wave length of the R.R. frequency, the recess terminating in an end wall 30.
  • Means are provided for applying an R.F. signal to the R.F. port; for example, a standard R.F. adapter may be attached by appropriate screw means to the block 12 utilizing a plurality of threaded apertures 24.
  • the stripline base member 50 may comprise a plastic material such as soft duroid strip 51 to which is applied thin copper sections, as will be set forth in greater detail below.
  • a first planar microstrip means is provided on the stripline base member 51 extending from the first end 40 of the housing and in register with the second deep recess, i.e., recess 34 in block member 32.
  • the first planar microstrip means comprises copper strips 52, 53, 54, and 55 on the side of the microstrip visible in FIG. 1, and copper strip portions 66 and 67 on the back side of the microstrip as shown in FIG. 2. It will be noted that copper portion 54 commences at the lower surface of the microstrip and flares upwardly to the longitudinally extending center section 55.
  • copper portion 66 starts near the upper edge or surface of the microstrip and then flares downwardly and flaring into the longitudinally extending copper strip portion 67, portion 67 extending to a point identified by reference numeral 36' which is in register with the end wall 36 of the recess 34.
  • reference numeral 36 which also is in register with end wall 36; reference numeral 36" indicating the end of the first planar microstrip means and the beginning of a second planar microstrip means which extends from that point to the right as shown in FIG. 1 throughout the remainder of the elongated flat stripline base member. Beginning at reference line 36", and proceeding to the right in FIG.
  • a pair of mixer diodes 70 and 71 are connected in series between copper portions 53', 57 and 52', as is shown in more detail in FIG. 3.
  • diode 70 is connected between center section 57 and the upper copper strip 52' and the diode 71 is connected from the lower copper strip 53' to the center copper strip 57.
  • the diodes are connected in the same sense, i.e., in series, and also the diodes are located directly in line with the axis of the R.F. port 25, i.e., axis 25'.
  • FIGS. 1 and 4 show attachment details of the I.F. output means to the microstrip; a suitable I.F.
  • the output connector 91 having an output connection means 92 with a portion 93 thereof having a conductor 94 electrically bonded to the copper section 62 on the microstrip.
  • the I.F. connector 91 further has a plurality of apertures 96 for use in attaching the I.F. connector to the mixer.
  • the two block members 12 and 32 are shown in abutting relationship with the elongated relatively shallow recesses 18 and 42 collectively defining the elongated enclosure extending from one end of the housing member to the other and forming therefore an enclosure for the elongated flat stripline base member 50.
  • the relatively deep enclosure 14 is clearly depicted in FIG. 5 and, through the use of dotted lines, the shorter but relatively deep recess 34 is also depicted.
  • the R.F. port 25 is shown extending completely through block member 12 and partially into block member 32 terminating at end wall 35.
  • the first planar microstrip means functions as a wave guide to microstrip transition to couple the local oscillator signal to the matched pair of mixer diodes 70 and 71.
  • the diodes bonded on the substrate are excited out of phase by the local oscillator signal; they are excited in phase by the R.F. input signal which travels down the R.F. port from the source of R.F. signals coupled to block 12 through the attachment means 24.
  • the result is a symmetry type hybrid junction in which the R.F. signal to local oscillator isolation is inherently high and independent of frequency.
  • the I.F. output is extracted by the microstrip low pass filter 58-62 which filter rejects the local oscillator energy. Due to the junction symmetry properties of the diodes, there will be no R.F. signal on the microstrip lines; consequently, the I.F. output filter has no impact on the R.F. signal matching. This contributes significant improvement to the band and conversion loss.
  • the present invention eliminates the prior art problems by using a frequency independent hybrid junction. Further, in the present invention the whole circuit can be built on a single substrate which permits low cost construction and very high reliability even in adverse environments.
  • a typical range of L.O. frequencies is 26 to 100 GHz
  • a typical range of R.F. frequencies is 26 to 100 GHz
  • a typical range of I.F. frequencies is 0 to 14 GHz.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Waveguide Connection Structure (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Superheterodyne Receivers (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
US06/364,289 1982-04-01 1982-04-01 Millimeter-wave stripline planar mixer Expired - Lifetime US4412354A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US06/364,289 US4412354A (en) 1982-04-01 1982-04-01 Millimeter-wave stripline planar mixer
EP83103016A EP0091042B1 (en) 1982-04-01 1983-03-26 Millimeter-wave mixer
DE8383103016T DE3364147D1 (de) 1982-04-01 1983-03-26 Millimeter-wave mixer
JP58055353A JPS58202604A (ja) 1982-04-01 1983-04-01 ミリ波用ストリツプライン・プレ−ナ・広帯域ミキサ

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/364,289 US4412354A (en) 1982-04-01 1982-04-01 Millimeter-wave stripline planar mixer

Publications (1)

Publication Number Publication Date
US4412354A true US4412354A (en) 1983-10-25

Family

ID=23433853

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/364,289 Expired - Lifetime US4412354A (en) 1982-04-01 1982-04-01 Millimeter-wave stripline planar mixer

Country Status (4)

Country Link
US (1) US4412354A (zh)
EP (1) EP0091042B1 (zh)
JP (1) JPS58202604A (zh)
DE (1) DE3364147D1 (zh)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4461041A (en) * 1983-01-05 1984-07-17 Zenith Radio Corporation Integrated RF receiver/waveguide
US4541124A (en) * 1982-06-08 1985-09-10 Thomson Csf Microwave mixer
US4590617A (en) * 1984-01-30 1986-05-20 Sperry Corporation Hermetically sealed planar structure for high frequency device
US4641369A (en) * 1984-11-29 1987-02-03 Trw Inc. Local oscillator and mixer assembly
US4654888A (en) * 1984-05-18 1987-03-31 Sharp Kabushiki Kaisha Image suppression mixer of the waveguide type
US4679249A (en) * 1984-02-15 1987-07-07 Matsushita Electric Industrial Co., Ltd. Waveguide-to-microstrip line coupling arrangement and a frequency converter having the coupling arrangement
US4864645A (en) * 1988-05-26 1989-09-05 The United States Of America As Represented By The Secretary Of The Army Harmonically pumped monolithic planar doped barrier mixer
US5062149A (en) * 1987-10-23 1991-10-29 General Dynamics Corporation Millimeter wave device and method of making
US5125110A (en) * 1990-10-17 1992-06-23 Valentine Research, Inc. Microstripline microwave mixer using waveguide filter
US6198912B1 (en) * 1996-06-18 2001-03-06 Siemens Information And Communication Networks, S.P.A. Frequency converter for the application on millimetric radio waves
US6624716B2 (en) * 2002-01-03 2003-09-23 Raytheon Company Microstrip to circular waveguide transition with a stripline portion
WO2003084053A2 (en) * 2002-03-28 2003-10-09 Farran Technology Limited 'an upconverter'
US7027833B1 (en) 2003-04-03 2006-04-11 The United States Of America As Represented By The Secretary Of The Navy Dual band superheterodyne receiver

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0185446A3 (en) * 1984-10-12 1988-03-30 British Aerospace Public Limited Company Transmitter/receiver
US4811426A (en) * 1987-05-07 1989-03-07 Martin Marietta Corporation Suspended stripline rat race mixer with simplified I. F. extraction
US4955079A (en) * 1989-09-29 1990-09-04 Raytheon Company Waveguide excited enhancement and inherent rejection of interference in a subharmonic mixer

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3584306A (en) * 1967-09-18 1971-06-08 George Ctirad Spacek High frequency converter
US4270224A (en) * 1979-03-01 1981-05-26 Thomson-Csf Microwave down converter
US4276655A (en) * 1979-10-29 1981-06-30 Sperry Corporation Integrated circuit planar high frequency mixer

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7704644A (nl) * 1977-04-28 1978-10-31 Hollandse Signaalapparaten Bv Mengelement.

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3584306A (en) * 1967-09-18 1971-06-08 George Ctirad Spacek High frequency converter
US4270224A (en) * 1979-03-01 1981-05-26 Thomson-Csf Microwave down converter
US4276655A (en) * 1979-10-29 1981-06-30 Sperry Corporation Integrated circuit planar high frequency mixer

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"A Broad-Band, Low Noise Receiver at W-Band" by Hu et al., 15-19, Jun. 1981. *

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4541124A (en) * 1982-06-08 1985-09-10 Thomson Csf Microwave mixer
US4461041A (en) * 1983-01-05 1984-07-17 Zenith Radio Corporation Integrated RF receiver/waveguide
US4590617A (en) * 1984-01-30 1986-05-20 Sperry Corporation Hermetically sealed planar structure for high frequency device
US4679249A (en) * 1984-02-15 1987-07-07 Matsushita Electric Industrial Co., Ltd. Waveguide-to-microstrip line coupling arrangement and a frequency converter having the coupling arrangement
US4654888A (en) * 1984-05-18 1987-03-31 Sharp Kabushiki Kaisha Image suppression mixer of the waveguide type
US4641369A (en) * 1984-11-29 1987-02-03 Trw Inc. Local oscillator and mixer assembly
US5503960A (en) * 1987-10-23 1996-04-02 Hughes Missile Systems Company Millimeter wave device and method of making
US5062149A (en) * 1987-10-23 1991-10-29 General Dynamics Corporation Millimeter wave device and method of making
US4864645A (en) * 1988-05-26 1989-09-05 The United States Of America As Represented By The Secretary Of The Army Harmonically pumped monolithic planar doped barrier mixer
US5125110A (en) * 1990-10-17 1992-06-23 Valentine Research, Inc. Microstripline microwave mixer using waveguide filter
US6198912B1 (en) * 1996-06-18 2001-03-06 Siemens Information And Communication Networks, S.P.A. Frequency converter for the application on millimetric radio waves
US6624716B2 (en) * 2002-01-03 2003-09-23 Raytheon Company Microstrip to circular waveguide transition with a stripline portion
WO2003084053A2 (en) * 2002-03-28 2003-10-09 Farran Technology Limited 'an upconverter'
WO2003084053A3 (en) * 2002-03-28 2004-03-18 Farran Technology Ltd 'an upconverter'
US20050042993A1 (en) * 2002-03-28 2005-02-24 Sean Cremin Upconverter
US7349676B2 (en) 2002-03-28 2008-03-25 Farran Technology Limited Upconverter
US7027833B1 (en) 2003-04-03 2006-04-11 The United States Of America As Represented By The Secretary Of The Navy Dual band superheterodyne receiver
US20060089115A1 (en) * 2003-04-03 2006-04-27 Goodman Daniel J Dual band superheterodyne receiver

Also Published As

Publication number Publication date
JPS58202604A (ja) 1983-11-25
DE3364147D1 (de) 1986-07-24
EP0091042B1 (en) 1986-06-18
EP0091042A1 (en) 1983-10-12
JPH0125242B2 (zh) 1989-05-17

Similar Documents

Publication Publication Date Title
US4412354A (en) Millimeter-wave stripline planar mixer
US6868258B2 (en) Structure for connecting non-radiative dielectric waveguide and metal waveguide, millimeter wave transmitting/receiving module and millimeter wave transmitter/receiver
US5107231A (en) Dielectric waveguide to TEM transmission line signal launcher
US6580335B1 (en) Waveguide-transmission line transition having a slit and a matching element
US6384694B1 (en) Dielectric line converter, dielectric line unit, directional coupler, high-frequency circuit mobile, and transmitter-receiver
US4096482A (en) Wide band monopulse antennas with control circuitry
EP0820114A1 (en) Multilayer dielectric line circuit
Meier Millimeter integrated circuits suspended in the E-plane of rectangular waveguide
US4573056A (en) Dipole radiator excited by a shielded slot line
US4641369A (en) Local oscillator and mixer assembly
KR100291767B1 (ko) 비방사성 유전체선로를 구비하고 있는 전자부품 및 이를사용하는 집적회로
CA2256283C (en) Non radiative dielectric waveguide having a portion for line conversion between different types of non radiative dielectric waveguides
US4406020A (en) Millimeter wave printed circuit mixer
US4644302A (en) Microwave power divider
US4270224A (en) Microwave down converter
KR100471049B1 (ko) 링 하이브리드 결합기를 이용한 비방사 유전체 도파관혼합기
US4480336A (en) Orthogonal hybrid fin-line mixer
US6931246B2 (en) Line coupling structure, mixer, and receiving/transmitting apparatus comprised of suspended line and dielectric waveguide
EP0827269B1 (en) Balance-type mixer
CN114050392A (zh) 功率合成器、高频模块和雷达物位计
US4864645A (en) Harmonically pumped monolithic planar doped barrier mixer
Breuer et al. A low cost multiplexer for channelized receiver front ends at millimeter waves
US4533886A (en) Self-biasing broadband frequency divider
US20220376375A1 (en) Waveguides
KR20010112034A (ko) 도파관-마이크로스트립 변환 구조를 이용한 전력 결합기

Legal Events

Date Code Title Description
AS Assignment

Owner name: HONEYWELL INC., MINNEAPOLIS, MN. A CORP. OF DE.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:HU, CHI P.;REEL/FRAME:003981/0358

Effective date: 19820330

STCF Information on status: patent grant

Free format text: PATENTED CASE

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, PL 96-517 (ORIGINAL EVENT CODE: M170); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 4

AS Assignment

Owner name: WATKINS-JOHNSON COMPANY, A CORP. OF CA, CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:HONEYWELL, INC.;REEL/FRAME:005004/0700

Effective date: 19880902

FEPP Fee payment procedure

Free format text: PAYMENT IS IN EXCESS OF AMOUNT REQUIRED. REFUND SCHEDULED (ORIGINAL EVENT CODE: F169); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, PL 96-517 (ORIGINAL EVENT CODE: M171); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 8

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Free format text: PAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Free format text: PAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 12TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M185); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 12

AS Assignment

Owner name: STELLEX MICROWAVE SYSTEMS, INC., A CALIFORNIA CORP

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:WATKINS-JOHNSON COMPANY, A CALIFORNIA CORPORATION;REEL/FRAME:008811/0760

Effective date: 19971107

AS Assignment

Owner name: FIRST UNION COMMERCIAL CORPORATION, VIRGINIA

Free format text: SECURITY INTEREST;ASSIGNOR:STELLEX MICROWAVE SYSTEMS, INC.;REEL/FRAME:008829/0085

Effective date: 19971031

AS Assignment

Owner name: STELLEX MICROWAVE SYSTEMS, INC., CALIFORNIA

Free format text: RELEASE;ASSIGNOR:FIRST UNION COMMERCIAL CORPORATION, AS COLLATERAL AGENT;REEL/FRAME:011855/0294

Effective date: 20010202